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在蒸渗仪中用张力计监测并严格控制土壤水势，研究不同程度的持续土壤水分胁迫对两个中熟水稻品种（组合）汕优６３和盐粳２号的生长发育和产量构成的影响。结果表明：在持续土壤水分胁迫下，①两品种生育前期叶面积的形成均受到抑制，且受抑程度与水分胁迫程度呈正相关，叶面积峰值出现较浅水层处理迟，生育后期叶面积下降较为迟缓；②两品种生育前期的分蘖发生受到抑制，在生育后期除了汕优６３在较轻程度的水分胁迫下分蘖数略高于浅水层处理外，两品种在其余各胁迫处理下分蘖的变化基本上不受胁迫处理影响；③随着胁迫程度的增加，两品种的株高降低，生育期延迟；④两品种产量下降的幅度与胁迫程度呈正相关，当土水势保持在－０．０２５～－０．０４５ＭＰａ时，汕优６３的减产幅度较盐粳２号大，而当土水势降到－０．０７０～－０．０７５ＭＰａ时，盐粳２号的减产幅度大于汕优６３，主要由于穗颖花数的减少。
In the lysimeter, the soil water potential was monitored with a tension meter and the soil water potential was strictly controlled to study the effects of different degrees of continuous soil water stress on the growth and yield components of two medium maturing rice varieties, Shanyou 63 and Yanjing 2. The results showed that under continuous soil water stress, the formation of leaf area of both varieties was inhibited at early growth stage, and the degree of inhibition was positively correlated with the degree of water stress. The peak of leaf area appeared later than that of shallow water layer, Slowed down; ②The early tillering of both varieties was inhibited, except for Shanyou 63 in tillering stage, the tillering number of Shanyou 63 was slightly higher than that of shallow water treatment, (3) With the increase of the degree of stress, the plant height of both cultivars decreased and the growth period delayed. (4) The decline of yield of both cultivars was positively correlated with the degree of stress. When the soil water potential remained at -0.025 ~ 0.045MPa, the yield reduction of Shanyou 63 was larger than that of Yanjing 2, while when the soil water potential dropped to -0.070 ~ -0.075MPa, the yield reduction of Yanjing 2 was greater than that of Shanyou 63, Reduction of the number of spikes.